The Hispanic population, the fastest growing ethnic minority in the US, has a high fertility rate and the potential for a high rate of preterm births (PTB). If the PTB rate continues to rise, it will have devastating effects on children and increase medical costs. In this renewal application of R01 NR00789-04, we propose to clarify the impact of acculturation of Hispanic women on PTB, and to assess the roles of psychosocial, physiologic, and genetic mediating factors in the relationships between acculturation and birth outcomes. Acculturation occurs as individuals adopt the attitudes, values, customs, beliefs and behaviors of another culture. Previous studies show a Hispanic Paradox in which relatively less acculturated Hispanics with intact social relationships exhibit better than expected health outcomes, despite low socio- economic status. Our current study supports this and indicates a preterm birth rate of 13.4 percent for the more acculturated women as compared to a PTB rate of only 4.7 percent for the less acculturated women. Inflammatory factors resulting from stress are higher in our more acculturated group, potentially increasing the risk of PTB. With renewed funding, we will examine these results by studying Hispanic pregnant women at 22-24 weeks gestation. Aim 1: Identify which acculturation factors predict immune and endocrine responses that are associated with PTB and LBW. Aim 2: Identify which components of acculturative distress mediate the contribution of acculturation factors on the immune and endocrine responses that predict PTB and LBW. Aim 3: Identify which components of the psychosocial protective factors mediate the contribution of acculturation factors to immune and endocrine responses that predict PTB and LBW. Aim 4: Identify pro-inflammatory cytokine gene polymorphisms that may affect TNF-1 and IL-1Ra and may mediate stress responses. This prospective, observational study will focus on 500 Hispanic women, ages 14-45 years, with a single intrauterine pregnancy. We will: 1) use self-report instruments to assess acculturative distress and psychosocial protective factors;2) measure acculturation in a multi-dimensional way;3) measure numerous stress and reproductive hormones, and inflammatory cytokines in the blood and their gene polymorphisms;4) assess maternal and infant outcomes through a review of medical records;5) analyze data through logistic regression and/or structural equation modeling. We will learn how acculturation affects biological responses. We plan to use psychosocial and biological risk data to focus interventions for those women most at risk. PUBLIC HEALTH RELEVANCE: The purpose of this renewal is to clarify the impact of acculturation of Hispanic women on preterm birth, using a multidimensional measure of acculturation and assessing the role of mediating factors in explaining the relationships between acculturation and birth outcomes. We will also examine whether our current evidence related to increased inflammation with more acculturation (English proficiency) is different by genetic predisposition of the inflammatory response (i.e. increasing the risk of preterm birth). Our understanding of the relation between acculturation and prematurity is vital in the process of implementing interventions to promote a healthy maternal and fetal outcome.